Conventionally, foods such as fresh poultry, fish, meat, and other foods which tend to exude fluids after packaging, are packaged for refrigerated display by employing a tray to receive the food. Generally, a transparent or translucent plastic film is wrapped and sealed around the food placed on the tray itself and the tray to provide a finished, sealed package. The tray provides structural integrity and acts as a reservoir for fluids. Ideally, the tray also serves as a moisture barrier.
One type of tray is generally constructed from compressed wood pulp. However, the structural integrity of this type of tray is diminished by the absorption of fluids from the product placed on the tray. Another type of tray is made from a non-absorbent material which can retain its structural integrity upon exposure to fluids and moisture. Suitable non-absorbent materials include thermoplastic materials, such as polyethylene, polypropylene, polystyrene, and polyvinyl chloride. Although trays made from thermoplastic materials as described above have several advantages in terms of cost, weight, aesthetics, durability, and other characteristics, the inability of these materials to absorb moisture often results in the accumulation of fluid exuded from the food product placed on the tray. The tray with the food product is customarily wrapped and optionally heat sealed with a transparent, flexible thermoplastic film so that the finished product may be displayed in a refrigerated display case in such a manner that the consumer may view the food product directly through the packaging. Accordingly, the accumulation of fluids in the tray surrounding the food product is undesirable because it results in an unsightly, unappetizing and therefore unappealing packaged product. Furthermore, and more importantly, although the package is sealed with a flexible transparent film the accumulated fluid may leak from the package. In addition, accumulated fluids may promote the growth of bacteria.
One approach to solving this problem has been to provide an absorbent pad between the upper surface of the non-absorbent tray and the food product. In theory, the pad will absorb the exuded fluids from the food product preventing the accumulation of free fluids within the package. Another proposed solution to the problem has been to provide a separate reservoir within the tray such that fluids exuded by the food product are drained away from contact with the product, generally by providing a retaining surface above the bottom wall of the tray. The retaining surface includes drain holes extending therethrough such that fluid drains from the product retaining surface and is retained above the lower wall of the tray. Examples of food trays and pads for use therewith are shown in U.S. Pat. Nos. 3,575,287, 4,275,811, 4,321,997, 4,410,578, 4,865,855, 4,929,480, 4,949,897 and WO 99/32286. The disclosure of each of the foregoing U.S. patents is hereby incorporated by reference.
The use of prior absorbent pads for the absorption of fluids from a packaged food product suffers from several disadvantages. Typically, after the pad is saturated with fluid it tends to stick to the food product and must be physically separated from the food product by the consumer after the package is opened. Because the pad is saturated with fluids exuded by the food product, this is a generally unappealing exercise.
The use of a separate fluid reservoir to separate and retain exuded fluids, suffers from other disadvantages. The construction of the food tray is complex, requiring at least two layers separated by a free space to serve as the reservoir. Further, it is difficult to keep the fluid within the reservoir when the package is upset from a level orientation. Thus, it is an object of the present invention to provide an absorbent core for use with food packaging and which is capable of absorbing all or substantially all of the fluid which may be exuded from a food product placed within the tray during its shelf life. It is another object of the present invention to provide an absorbent core which may be used in a food package to maintain an aesthetically pleasing and sanitary package. It is yet another object of the present invention to provide an absorbent core which upon absorbing fluid from the food product prevents or at least minimizes rewet, or fluid contact between the fluid and the food product.